Fig. 1: FMD/STS enhances vitamin C anticancer activity in KRAS-mutant tumors.

a Viability of KRAS-mutant and b KRAS-wild-type cancer cells treated for 48 h with STS with or without vitamin C; HCT116 (n = 9); DLD1, CT26, H23, and PANC1 (n = 4); H727 (n = 3); SW48 and HT29 (n = 4); PC-3 (n = 3); COV362 and CCD841CoN cells (n = 4). P values were determined by two-sided unpaired t-test. DLD1: exact P value = 0.0000005; CT26: exact P value = 0.00000009; H23: exact P value = 0.00001; H727: exact P value = 0.000005; PANC1: exact P values = 0.0000001 (CTR vs CTR + Vit C), 0.00000000004 (CTR vs STS + Vit C). c Viability of HT29 cells infected with empty backbone (EB; n = 3, n = 4 in STS + Vit C 700 µM) or KRASV12 vector (n = 6, n = 7 in STS + Vit C 125 µM, n = 8 in CTR + Vit C 700 µM and STS + Vit C 350 µM, n = 9 in STS + Vit C 700 µM); SW48 WT (n = 4) and SW48 KRASV12 (n = 4, n = 3 in CTR and STS) treated for 48 h with STS with or without vitamin C. P values were determined by two-sided unpaired t-test. SW48: exact P values= 0.000008 (STS + Vit C 350 µM wt vs STS + Vit C 350 µM KRASV12), 0.000005 (STS + Vit C 700 µM wt vs STS + Vit C 700 µM KRASV12). d Tumor growth of HCT116-derived xenograft (n = 8) and e CT26-derived allografts (n = 13 in Ad libitum and Vit C, n = 14 in FMD and n = 10 in FMD + Vit C). Tumor volumes at multiple time points (left) and before euthanasia (right) are presented. P values were determined by One-way ANOVA with Tukey’s post analysis. HCT116: exact P value = 0.000000002 (Ad libitum vs FMD + Vit C); CT26: exact P values = 0.0000000001 (Ad libitum vs FMD + Vit C), 0.00008 (Ad libitum vs Vit C), 0.0000007 (Ad libitum vs FMD). f Tumor growth of CT26-luc-derived orthotopic model (n = 7 in Ad libitum and Vit C, n = 6 in FMD and n = 5 in FMD + Vit C). Total photon effluxes over tumor regions were measured. P values were determined by two-sided unpaired t-test. All data are represented as mean ± SEM, n = independent experiments.